Knowledge Bank

The ground state spectrum of the asymmetric hydroxyl internal motion in ethyl alcohol has been studied in the millimeter-wave region. The spectrum of and interactions between the three different OH torsional sub-states or rotational isomers (trans, gauche + and gauche-) are discussed. Approximately 1000 transitions have been assigned to the three different torsional substates including many with significant deviation from a standard asymmetric rotor pattern. This work extends the previous trans $state1$ and gauche $states2$ analyses and provides experimental data for a more complete formulation of a molecular Hamiltonian for the asymmetric $hydroxy1$ internal rotation.